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Kansas State Agricultural College. 

Division of Agriculture. 
Veterinary Department. 



Blackleg and Vaccination. 

BY 

DR. F. S. SCHOENLEBER. 



MANHATTAN, KANSAS, 
December 31, 1909. 



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Blackleg and Vaccination. 



Blackleg, also called black-quarter and quarter-ill, and some- 
times described in textbooks under the name of symptomatic 
anthrax, is a disease of young cattle caused by a germ, Bacillus 
chauvxi, and in Kansas causes a greater loss than any other 
disease of young cattle. 

Foreign veterinary writers state that blackleg occurs among 
sheep and goats, but if it ever occurs naturally among animals 
other than young cattle, it is extremely rare. 

Conditions Favoring Blackleg. It is the universal ex- 
perience of stockmen that blackleg, as a rule, attacks young 
cattle that are in the best physical condition, particularly if 
they are gaining rapidly in flesh and are on excellent pasture, 
or are being fattened for the market on dry feed. By some 
stockmen it is thought that if young cattle are losing flesh 
rapidly they are also more likely to contract blackleg. A 
thrifty or fat condition of young cattle is favorable to the de- 
velopment of blackleg, and the only well-recognized condition 
that favors the disease. Sex or breed does not seem to make 
any diff'erence in the susceptibility to blackleg. 

Age. Many cases of blackleg have been reported in suckling 
calves from two to three weeks old, but the disease is most 
likely to attack calves between six and eighteen months of age. 
After two years of age there is little danger, although a few 
cases are reported. Above three years of age blackleg is ex- 
tremely rare, but does occasionally occur in aged cattle. 

Symptoms. One of the first symptoms usually noticed is 
that the sick animal remains apart from the herd, usually lying 
down and ruminating (chewing the cud) . If the animal moves 
around it appears lame and stifl" in one leg and moves the 
aff'ected leg in a stiff and awkward manner. Exercise fre- 
quently causes some of the stifi'ness to disappear. Sometimes 
the disease affects more than one leg, and in some cases the 
neck is stiff, or the animal is stiff all over, or in one-half of the 
body only. 

When examined closely the muscles of the affected part or 
quarter are found to be swollen and tense. At first the swell- 

(3) 



4 Kansas State Agricultural College. [Div. of Agr. 

ing is small and painful, but as it rapidly increases in size the 
tenderness disappears and in a few hours the circulation is 
arrested and the part becomes cold and painless. This swelling 
is found to contain gas, which is shown by a drum-like feeling 
and a peculiar crackling or spongy sound when firmly pressed 
or rubbed with the hand. The presence of a large muscular 
swelling, which emits a crackling sound on pressure, is a char- 
acteristic symptom of blackleg. These swellings occur on the 
brisket and neck. They do not occur on the legs below the 
knees or hock joints, and are extremely rare on the belly. If 
the swelling is lanced a dark red, frothy, bloody fluid bubbles 
out. This fluid swarms with blackleg germs. 

In the early stages the calf has a fever, the temperature 
often running to 105 degrees, but as the disease progresses 
toward death the temperature falls below normal (101 to 102 
degrees). At first the mucous membranes, particularly of the 
eye and nostril, are congested and red, but later they have a 
dull leaden color. 

Animals suffering from blackleg are often easily excited in 
the early stages, and if driven and disturbed will sometimes 
fight viciously. After an animal afl'ected with blackleg gets 
down and unable to rise there is often some bloating noticed, 
particularly on the left side, but this bloating is due to indi- 
gestion, which may be induced by lying in one position. The 
bowels are usually constipated, a small quantity of dark- 
colored and rather hard dung being passed. Death usually 
occurs in from six to forty-eight hours after sickness is ob- 
served. 

Post-mortem Appearances. Practically the only abnormal 
condition noted in an animal that has died from blackleg is the 
altered appearance of the affected muscles. The muscles look 
as if badly bruised and filled with thick, dark blood and gases. 
The gas is noticed particularly in the connective tissue and 
blood, and occurs in bubbles. The connective tissue of the 
affected region often has a jelly-like appearance. Decompo- 
sition of the affected tissues and the contents of the digestive 
organs occurs rapidly after death and the body is soon badly 
bloated. 

Bodies of animals dying from blackleg should be 
burned, or buried deeply, and not left on the surface of 
the ground to spread the infection. 



Vet. Dept.] Blackleg and Vaccination. 5 

Season of tke Year. Blackleg occurs at all seasons of the 
year. Reports show that in May and June and in September 
and October are the seasons when the greatest losses occur. 
The mortality from blackleg shows the heaviest losses in those 
seasons when the young animals as a rule are making the most 
rapid gains in flesh. In May and June young cattle are usually 
making excellent gains on the fresh pastures; in July and 
August there is generally a slight falling off in flesh, due to flies 
and the hot, dry weather. Later, as the grass matures and 
the cooler weather comes on, young cattle are usually in the 
best flesh of the year, and it is during this period of the year 
that the greatest losses from blackleg occur. The better phys- 
ical condition seems to offer the most plausible explanation of 
the increased prevalence of blackleg at these seasons. There 
is also a slight increase of blackleg during the month of Feb- 
ruary. 

Manner of Infection. Blackleg is generally considered 
by veterinary authorities to be a wound-infection disease. It 
is possible if infection with the germs of blackleg takes place 
through a wound that sores in the mouth, which are frequent 
in young cattle while they are cutting and shedding their 
teeth, may offer favorable places for infection. Experiments 
made oy this department by drenching susceptible calves with 
infectious material have not been successful in producing the 
disease. Injecting the material under the skin does not always 
produce the disease. Another circumstance which is rather 
against the theory of wound infection is, that it is quite a fre- 
quent practice among stockmen to dehorn a bunch of calves as 
soon as blackleg appears, as there is a common opinion that 
this operation tends to stop the spread of the disease. If 
wound infection is a common method of contracting the dis- 
ease, dehorning an infected bunch ought to offer favorable con- 
ditions for the spread of blackleg, but it does not seem to do so. 

Period of Incubation. This is the length of time that 
elapses after the germs are introduced before signs of the dis- 
ease appear, and vary, according to circumstances, from five 
hours to four or five days. 

Immunity. This is the power which an animal possesses 
to resist disease. Immunity may be natural or acquired ; that 
is, an animal may possess immunity when bom, or may 
acquire immunity afterwards. Swine possess a natural im- 



6 Kansas State Agricultural College. [Div. of Agr. 

munity towards blackleg; calves do not, but as they get older 
— from two to three years — they acquire immunity. This is 
called natural immunity. Immunity against blackleg may be 
acquired by having a mild form of the disease or by vaccina- 
tion. Calves are vaccinated to give immunity against blackleg. 

Calves seem to possess some natural immunity against black- 
leg. This natural immunity varies with different individuals, 
with different herds of cattle, with the physical condition of 
the animal, and apparently with the season of the year. There 
is no way of detecting the degree of immunity, except that they 
do not acquire blackleg when infected with germs of the dis- 
ease. This varying individual immunity is also shown by the 
fact that when a dangerously strong blackleg virus is injected 
into susceptible calves, under the same conditions, a few will 
resist infection and will not contract the disease. 

Immunitj^ also seems to vary with different bunches of 
cattle. Experiments in vaccination indicate that a vaccine that 
has been carefully prepared and tested, when sent out and used 
by different individuals upon more than 10,000 head of cattle, 
will occasionally cause the loss of cattle as a direct result of 
vaccination. This would indicate that the natural immunity in 
these cattle was very weak. These results, however, are al- 
ways complicated by the possibility that the vaccine was not 
properly used. 

Blackleg Vaccine. Blackleg vaccine is made by taking the 
bruised looking diseased flesh from an animal affected with 
blackleg. This meat is cut into thin strips, dried, and ground 
into a fine powder. This powder is wet with distilled water 
and weakened or attenuated by heating from six to seven 
hours. The higher the temperature and the longer the vaccine 
is heated the weaker it becomes. After being weakened by 
heat the vaccine is again ground into a very fine brownish 
powder, and is sent out in this form. Two kinds of vaccine are 
made and distributed by this department. Each vaccine is put 
up in ten and twenty-five dose packets only. These are doses 
for yearlings or over. A single vaccine that requires but one 
vaccination is put up in red paper packets, and a double vaccine 
that requires two vaccinations about ten days apart is put up 
in white and yellow paper packets. Both single and double 
vaccine packets are plainly labeled, and on the back of the 
packet is stamped the date by which time the vaccine should 
be used, as it loses strength after a few months. 



Vet. DepL] 



Blackleg and Vaccination. 



Single vaccine is made by heating the powdered blackleg 
meat for six and one-half hours at a temperature of 92 to 93 
degrees. It is wrapped in red paper, in ten and twenty-five 
dose packets. The single vaccine requires vaccinating but 
once. 

The double vaccine consists really of two vaccines. The 
first, a very weak vaccine, is made by heating the pulverized 
blackleg meat at a temperature of 99 to 100 degrees for six 
and one-half hours. This first vaccine is put up in white 




papers, and, being a very weak vaccine, is intended to prepare 
the animal's system for the second, which is a strong vaccine. 
The second of the double vaccine is made by heating the pul- 
verized blackleg meat for six and one-half hours at a tempera- 
ture of 88 to 89 degrees, and is put up in yelloM^ paper packets 
plainly marked. 

The vaccine prepared by this department is made with great 
care, and is always tested upon some calves before being sent 
out. 

Vaccinating Instruments. To use the vaccine it is neces- 



8 



Kansas State Agricultural College. [Div. of Agr. 



sary to have a hypodermic syringe, mortar and pestle, gradu- 
ate, funnel and filter paper. Such an outfit can usually be 
purchased upon the market for four or five dollars. To accom- 
modate Kansas stockmen this department keeps a supply of 
vaccinating outfits on hand. By purchasing them in large 
quantities we are able to furnish them for $3.50, complete. In 
some localities several stockmen own an outfit in common. The 
department also hasi on 
hand supplies for outfits, 
such as needles, plungers, 
filter paper, etc., which are 
supplied at cost. The outfit 
which we supply comes in 
a neat hardwood case. The 
accompanying illustration 
shows the box and its con- 
tents. 

The Syringe. The vacci- 
nating syringe holds five 
cubic centimeters; that is, 
sufficient for five yearling 
calves. The graduations 
are marked on the plunger 
stem. There is also on the 
stem a small nut which can 
be screwed down so that 
the dose can be accurately 
determined. The plunger 
of the syringe should be ad- 
justed so that when the in- 
side of the syringe is wet 
it will work smoothly. This 
adjustment can be regu- 
lated by pushing the 
Diunger clear down and 
turning the thumb ring to 
to the right or left, to 
tighten or loosen the 
plunger. 

There is a screw cap {h) 
which should be kept on the 




Vet. Dept.] Blackleg and Vaccination. 9 

syringe when not in use, to protect it from dirt. A small 
washer should be kept on the nipple where the needle screws 
on, to prevent the vaccine leaking. Two needles (c) that 
screw on are supplied with each syringe. The needle points 
should be kept sharp by using an oilstone if necessary. A 
small wire (d) is furnished with each needle, to be inserted 
when the needle is not in use; this wire protects the point of 
the needle and keeps the dirt out. Do not put oil in the syr- 
inge, as it will ruin the rubber plunger and rubber washers at 
the end of the barrel. 

Sterilizing the Instruments. It is very important that 
the vaccinating instruments be kept as clean as possible. After 
using the syringe it should be disinfected by filling with a 
five-per-cent solution of carbolic acid or a two-per-cent solu- 
tion of creolin. This should be left in the syringe for a few 
minutes, then the syringe should be rinsed with clear water 
that has been boiled. The bottle, funnel and graduate should 
be treated in the same manner. Do not pour boiling water on 
the syringe, graduate, funnel or bottle, as they are liable to 
break. They may be placed in warm water which can be 
gradually brought to the boiling point. 

If blackleg exists in the herd at the time of or just previous 
to vaccinating, the needle should be disinfected after each in- 
jection by dipping it into a strong disinfecting solution, such as 
a five-per-cent solution of carbolic acid. This is to prevent in- 
fecting other calves, should a calf having blackleg be vacci- 
nated. Otherwise, other calves might become inoculated from 
the infected needle. Should any calves show symptoms of 
blackleg, they should be left until the last, and the instruments 
be thoroughly disinfected after vaccinating them. 

Age to Vaccinate. Young cattle can be vaccinated at any 
age, although it is rarely advisable to vaccinate calves under 
four weeks old. Calves or young catlle should not be vacci- 
nated when they are suffering from any debilitating disease, or 
when debilitated from shipping, driving, or a lack of feed or 
care. It is not advisable to vaccinate animals at the time they 
are dehorned or castrated, nor in cold, stormy or wet weather 
unless they are thoroughly protected. Calves under one year 
old should be vaccinated frequently — every three or four 
months, if possible. The younger an animal the shorter seems 
to be the period of immunity conferred by vaccination. After 



10 Kansas State Agricultural College. [Div. of Agr. 

the calf is one year old vaccination gives immunity for about 
five to six months; after five months, however, the immunity 
is much less, and while it is generally accepted that vaccinating 
twice a year will protect them, from observations made by this 
department vaccinating three times a year gives much better 
results. An excellent plan would be to vaccinate at one month, 
four months, eight months, one year, sixteen months, and 
twenty months. Frequent vaccination gives best results. 

Kind of Vaccine to Use. This department supplies two 
vaccines — a single and a double. The single vaccine may be 
said to be about half way in strength between the first and 
second of the double. We ordinarily recommend the double 
vaccine, as it is a little safer to use and gives a little greater 
immunity or protection against blackleg than the single. If the 
calves are pure bred or in excellent condition, it is always ad- 
visable to use the double vaccine. This is especially true of 
calves that are on full feed. Under such conditions we recom- 
mend using the first of the double vaccine, after about a week 
or ten days use the single, then in ten days more the secohd of 
the double vaccine. Vaccinating with both single and double 
vaccine gives excellent results. If the number of calves to 
vaccinate is large, cattlemen usually prefer to use the single 
vaccine, as it saves the trouble and expense of handling the 
cattle twice. 

When blackleg already exists in a bunch of young cattle, we 
advise using the single vaccine and in ten days the second of 
the double. 

Confining the Animals. About the best arrangement for 
confining calves for vaccination is a narrow chute, where they 
can be closely crowded in. If many calves are to be vacci- 
nated, a chute that will hold forty to fifty is very convenient. 
A footboard along one side, at a convenient height for the oper- 
ator to stand upon, is excellent. With such an arangement, and 
sufficient help to fill the chute quickly, 300 head an hour can be 
vaccinated. When there are only a few calves, a narrow stall, 
stanchion or chute makes a convenient place to confine them. 

Place to Vaccinate. There are several places on the an- 
imal where vaccination is commonly practiced. They are the 
shoulder, neck, tail, ear, and brisket. A good many vaccinate 
in the shoulder. This is a convenient place, as the skin is thin 
and there is considerable loose tissue beneath the skin. The 



Vet. Dept.] 



Blackleg and Vaccination. 



11 



objection to vaccinating in the shoulder is the danger of stick- 
ing the needle into the flesh or muscles which cover the 
shoulder deeply. A 
convenient place to 
vaccinate is beneath 
the skin of the neck, 
just in front of the 
shoulder. The skin is 
thin and loose in this 
region. The needle 
can be easily and p. ^ 

quickly inserted ; there 
is little danger of sticking the needle into the flesh and no dan- 




ger of the vaccine leaking out. 




Fig. 2. 



Preparing Vaccine for 

Using. These directions 
assume that the vaccine 
used is the first of the 
double. Both the single 
and the second of the double 
are prepared in precisely 
the same manner. 

Having the utensils and 
instruments perfectly clean, 
empty the contents of one 
or more of the packets in 
white paper, marked "first 



vaccine," into the mortar, and add a few drops of boiled but 
cooled water to this, and with the pestle grind or rub it thor- 
oughly into a thin paste; 
then add for each ten-dose 
package of vaccine used ten 
cubic centimeters of the 
boiled water, or, if the twen- 
ty-five dose packages have 
been used, add twenty-five 
cubic centimeters for each 
packet ; add the water gradu- 
ally, and continue to stir the 
mixture with a grinding mo- 
tion of the pestle in the mor- 
tar. Then fold a filter paper. Fig. 3. 




12 Kansas State Agricultural College. [Div. of Agr. 

doubling it first so as to form a half a circle, as shown in 
figure 1 ; then fold a second time, at right angles to the first, 
as shown in figure 2. Then open one side, and the filter paper 
will form a cone (figure 3) that fits exactly the inside of the 
glass funnel, in which it should be placed, and wet with some 
of the boiled water. Allow all the water to drain off and dis- 
card it. The funnel containing the filter paper is now placed 
in or over the bottle with the ground-glass stopper. Stir the 
vaccine which has previously been prepared in the mortar 
thoroughly, and then pour into the filter. Practically all of the 
liquid will pass through the filter, leaving the brown vaccine 
sediment in the filter. The filtered vaccine should be clear, or 
very slightly straw-colored. Should it be dark colored, or any 
sediment in it, there is probably a hole in the filter paper, and 
it must be refiltered through a new filter paper. The vaccine 
should be very carefully filtered until it is clear or slightly 
straw-colored. The straw-colored liquid is the material used 
for vaccination. Burn the filter paper containing the sedi- 
ment ; also burn the papers that the vaccine is wrapped in. 

Immediate Effects of Vaccination. If the vaccine is 
properly prepared and used, there are no visible effects follow- 
ing vaccination. The only way of telling whether the vaccine 
has taken effect is that the animals do not contract blackleg. 

Cost of Vaccine and Outfit. The vaccine is put up in ten 
and twenty-five dose packets, and costs two cents per dose. 
Vaccinating outfits complete, $3.50. All orders should be ad- 
dressed to the Veterinary Department of the Kansas State 
Agricultural College, Manhattan, Kan. 



Vet. Deyt.'] Blackleg and Vaccination. 13 



SUMMARY. 

Blackleg is a germ disease, attacking young cattle from two 
or three weeks to two years old. It occasionally attacks older 
cattle. 

The greatest loss occurs between the ages of six and eigh- 
teen months of age. 

Calves that are in thrifty condition or fat are most likely to 
contract blackleg — particularly calves that are being fed for 
baby beef. 

The greatest losses from blackleg occur during the months 
of May and June, and September and October. 

The average loss among unvaccinated calves is probably be- 
tween four and five per cent. Vaccination will reduce this loss 
to less than four-tenths of one per cent. 

The younger calves are the shorter is the period of im- 
munity. Young calves should be vaccinated every four or five 
months. 

In vaccinating the vaccine should be filtered until it is clear, 
and care exercised not to inject the vaccine into the flesh, but 
into the loose tissue just beneath the skin. 

Calves should not be dehorned or castrated at the same time 
they are vaccinated. 

The Veterinary Department, Kansas State Agricultural Col- 
lege, Manhattan, Kan., furnishes blackleg vaccine, either single 
or double, to stockmen of Kansas for two cents per dose, to 
cover cost of making and distributing. Vaccinating outfits, 
complete, can be furnished for $3.50. 



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